An Etymological Dictionary of Astronomy and Astrophysics

A part that is cut off or separated.
A distinct part or subdivision of anything. → cross section; → intersection

Etymology (EN): From M.Fr. section, from L. sectionem “a cutting, division,” from secare “to cut;” PIE base *sek- “cut” (cf. O.C.S. seko, sesti “to cut,” Lith. isekti “to engrave, carve;” O.S. segasna, O.E. sigðe “scythe;” O.E. secg “sword,” seax “knife, short sword”).

Etymology (PE): Sekanj “a scraping, shaving,
cutting,” cognate with Pers. šekast-, šekastan “to break;” Av. skand- “to break,” Skt. khand- “to break,” khanda- “piece;” Pers. dialect Tabari šag “a special razor used to make incisions in the walls of unripe opium poppies in order to extract the milky sap,” may be related to PIE *sek- “cut,” as above.